LABIA TAE 



317 



upper ones are male, so that a bee sucking nectar, and working up from below, 

 regularly crosses separate stocks. Humble-bees actually behave in this way. Her- 

 mann Miiller points out that they work upwards on the unilateral inflorescence with 

 the greatest regularity, without missing a single flower. 



Should insect-visits fail, automatic self-pollination is only occasionally effected, 

 the stigma sometimes brushing the anthers while still covered with pollen. 



MacLeod says that gynodioecious plants occur in Luxemburg. 



Schulz observed occasional perforation by humble-bees. 



Fig. 343. Teucrium Scorodonia, L. (after Herm. Mailer). (i) Flower in the first (male) stage. 

 (2) Do., at the beginning of the second (female) stage. (3) Do., at the end of the second stage. 



Visitors. Herm. Mtiller (H. M.) and Buddeberg (Budd.) give the following 

 list. 



A. Diptera. Syrphidae : i. Eristalis nemorum Z., po-dvg., occasionally 

 effecting pollination by chance (H. M.). B. Hymenoptera. Apidae : 2. Antho- 

 phora quadrimaculata Pz. $ and $, skg. (H. M., Budd.) ; 3. Bombus agrorum F. 

 g and ?, very numerous, skg. (H. M., Budd.); 4. B. hypnorum L. $ and 5, skg. 

 (H. M.); 5. B. lapidarius Z. ^, do. (H. M., Budd.); 6. B. muscorum F. 51, do. 

 (H. M.) ; 7. B. pratorum Z. 5 and ?, freq., skg. (H. M.) ; 8. B. sylvarum Z, $, skg. 

 (Budd.); 9. Halictus morio F., creeping into the flowers (Budd.); 10. Osmia 

 aurulenta Pz. 5, skg. (Budd.); 11. Psithyrus barbutellus K. J, in large numbers, skg. 

 (H. M.) ; 12. Saropoda bimaculata Pz. 5 and J, very common, skg, (H. M.). 



Alfken saw 10, and Hoppner 11 bees at Bremen. 



Alfken i. Bombus agrorum i^. 5 ; 2. B. arenicola Ths.\ 3. B. proteus GersL^; 

 4. B, sylvarum Z. 5; 5. B. variabilis Schmiedekn. 5; 6. Megachile willughbiella ^. 5 ; 

 7. Podalirius borealis Mor. $ and J ; 8. P. furcatus Pz. $ ; 9. P. vulpinus Pz. 5 

 and J; 10. Psithyrus vestalis Fourcr. }, skg. Hoppner i. Apis meUifica Z. ^\ 

 2. Bombus agrorum F. 5 ; 3. B. arenicola Ths. 5 ; 4. B. hortorum Z. ; 5. B. lapi- 

 darius Z. ; 6. B. sylvarum Z. ; 7. Eucera difficilis (Duf.) Per. ; 8. Podalirius borealis 

 Mor. 5 and J; 9. P. furcatus Pz. 5 ; 10. P. retusus Z. 5; 11. P. vulpinus Pz. 5. 



The following were recorded by the observers, and for the localities stated. 



Knuth (Westphalia), the honey-bee, in very large numbers, skg. Loew (Berlin 

 Botanic Garden), the humble-bee Bombus terrester Z. J, skg. Schenck (Nassau), the 

 bee Anthidium manicatum Z. MacLeod (Pyrenees), 3 humble-bees (Bot. Jaarb. 

 Dodonaea, Ghent, iii, 1891, pp. 337-8), (Flanders), 5 bees (i. Apis mellifica Z. 5, 

 freq.; 2. Bombus terrester Z., very freq.; 3. B. muscorum F. do.; 4. Coelioxys 

 conica Z. ; 5. Eucera longicornis Z.), and 2 butterflies (Epinephele janira Z., and 



